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That´s just wonderful
Research and activities of the Group for Applied Physics with Accelerators
Manfredo Harri TabacniksInstitute of Physics, University of São Paulo
Group for Applied Physics with AcceleratorsGrupo de Físca Aplicada com Aceleradores
Instituto de Física USP
Dr. José Fernando D. Chubaci
Dr. Juan Carlos Acquadro ( col )
Dr. Manfredo Harri Tabacniks
Dr. Marcel DL Barbosa ( tec )
Dr. Márcia de Almeida Rizutto
Dr. Nemitala Added
Dr. Nilberto Hedder Medina ( col )
Dr. Raphael Liguori Neto
•Alessandro Alves da Silva - Dr
•Flor - Dr
•Márcia Regina Attie - Dr
•Jessica F. Curado - IC
•Jim Aburaya - Ms
•Regina Reiko - Dr
•Walter A. Santos Jr. - IC
•Viviane Silva Poli - MS
students
main objectives
Provide and develope accelerator based techniques for science and industry.
• Install, maintain, upgrade and provide accelerator based techniques for the analysis and modification of materials (equipment, softwares, databases..) and make them accessible to the scientific community including “non nuclear” scientists.
• Work for the development of these same techniques .
facilities - LAFNLaboratório Aberto de Física Nuclear
8.0 MV NEC Pelletron tandem accelerator with carbon foil stripper; 32-cathode SNICS ion source; duoplasmatron ion source.
External beam setup for analysis and ion implantation of samples in air.
Multi-use, 1m diameter vacuum chamber for HI-RBS and HI-EE-ERDA.
External beam PIXE-PIGE setup. 0.5mm Al exit window.
LAMFI Laboratório de Análise de Materiais por Feixes Iônicos
1.7 MV NEC (5SDH) Pelletron tandem accelerator with N2 stripper; RF/Rb ion source He- beam and a SNICS II source for H -, Li -, O -, Si -, and other beams .
Multi use vacuum chamber for RBS, PIXE, channeling and ERDA analysis with optional external beam. 5DF goniometer, computer based data acquisition and control system.
PIXE chamber optimized for air pollution analysis with 2 Si(Li) detectors, 18 position sample holder, computer based data acquisition and control system.
analytical techniques
M
E o
MERDAElastic Recoil Detection Analysis
X ray
H+
PIXEParticle Induced X ray Emission
ray
H+
PIGEParticle Induced Gamma ray Emission
RBSRutherford Backscattering Spectrometry
M Eo
E'M
analytical techniques
M
Eo
M
Etot = Ewindow + Egas + Eres
M
HI-EE-ERDAHeavy Ion EE Elastic Recoil Detection Analysis
analytical techniques
RBS Rutherford Backscattering SpectrometryERDA Elastic Recoil Detection Analysis
absolute atomic concentration: atoms/cm2 no need for calibration: first principlesdepth profileshigh sensitivity: < 1012 Au/cm2
quick: 10-20 minsensitive to layer topography: ?
PIXE Particle Induced X ray EmissionPIGE Particle Induced Gamma ray
Emission
absolute atomic concentration: atoms/cm2 need calibrationhigh sensitivity: ppmquick: 10-20 min
for the analysis of all elements of the
periodic table
AMS Accelerator Mass Spectrometry
extremly high sensitivity: 1: 1014 relative isotopic concentration no need for calibration
External beam for non vacuum applications
LAMFI main facility users
GEPA Group for Air Pollution Studies, IFUSP. Coordinator: Prof. Dr. Paulo E. Artaxo (40%, ~1500 PIXE analysis / year)
LSI Laboratory of Integrated Systems; Department of Electric Engineering, EPUSP. Coordinator: Prof. Dr. Nilton Itiro Morimoto (20%, ~400 RBS analysis / year)
LMM Laboratory of Magnetic Materials, IFUSP. Coordinator: Prof. Dr. Frank P. Missell (20%, ~400 RBS analysis / year)
OTHERS Calibration, tests and graduate and undergraduate courses. Other users from IFUSP and other research institutions. (20%, ~400 PIXE and RBS analysis / year)
over 50 research
projects / year
Collaborations
Faculdade de Odontologia, USPInstituto de Eletrotécnica, USP.Instituto de Física Gleb Wataghin, UNICAMPInstituto Nacional de Pesquisas Espaciais, INPE.Instituto de pesquisas Energéticas e Nucleares, IPENInstituto de Geociências, USPMuseu de Arqueologia e Etnologia - USP
Australian National UniversityUniversidade Federal Fluminense, RJUniversidade Estadual de Londrina
AMS project
research projects
• Experimental curves for energy loss of ions in matter
• Effects of thin film roughness on RBS analysis
• Characterization of thin films containing Li atoms
• AMS of geological samples
• Elementary analysis of teeth enamel and dentine
• Standardization of thick target substrates for PIXE analysis
• Optimization of HI-ERDA parameters for the analysis of thin films
• Modification of Si devices by high energy proton implantation
• High energy ion induced defects in biological materials
• Production of 102Ru radioctive sources
• Numerical simulation of E-E ERDA spectra
• Sr/Ca in shells as an environmental temperature sensor
• Deep nitrogen profiling in steel samples
• RBS analysis with Li beam
Typical PIXE X-ray spectra for enamel from human, swine and cattle teeth, using 12 MeV external proton beam.
External beam PIXE-PIGE analysis of teeth enamelM.A. Rizzutto, M.H. Tabacniks, N. Added, R. Liguori Neto, J.C. Acquadro, Institute of Physics, University of São Paulo, São Paulo, Brazil
T.R.C.F. Oliveira, R.A. Markarian, M. Mori Faculty of Dentistry, University of São Paulo, São Paulo, Brazil
M. M. Vilela Institute of Electrotechnique and Energy, University of São Paulo, São Paulo, Brazil
External beam PIXE-PIGE analysis of teeth enamel
100
1000
10000
100000
1000000
Ca P Cu K Cl Zn Fe Ti Sr V Mn Zr
atomic element
wei
ght c
once
ntra
tion
( µg
/ g
)
human
swine
cattle
Trace element weight concentration (in ppm) in enamel of human, swine and cattle teeth. Lines on top of each bar indicate sample mean standard deviation. Data were normalized to Ca (24.4%) concentration
in hidroxy-apatite with 0.4% water.
“Padronização de matrizes para análise de amostras espessas pelo método PIXE” Jim Heiji Aburaya
Desenvolver metodologia de diluição e padronização de amostras em pó para análises PIXE como amostra espessa sem os habituais problemas de elementos invisíveis (Z < 11).
Diluição da amostra em ácido bórico, HBO3 e calibração do PIXE por meio de fatores de correção de amostra espessa.
Biparametric ERDA spectra E x E: LiO/LiONi on C using58 MeV Cl beam.
(Sample from Alexandre Urbano, DFGW - UNICAMP)
a)
Cl
OC
Li
LiO/LiONi/C
ERDA analysis of light elements in heavy matricesN.Added, J.C. Acquadro, R. Liguori Neto, M.A. Rizutto, J.F. Chubaci, M.H. Tabacniks (IFUSP)
Au - 50Å
Ta - 50Å
AlNO - 10 to 1000 Å
Si
Robin Round characterization of the thickness and composition of thin to ultra-thin AlNO films (Samples provided by Dr. Nuno Barradas, ITN - Portugal)
International Atomic Energy Agency Research Contract No, 11317/RO/Regular Budget Fund
a) Energy spectrum for Al recoils from samples S5 and S6, nominally 1000 and 10 A thick; b) Energy spectrum for Al recoils from samples S2 and S3, nominally 10 and 100 A thick; c) Biparametric spectra E x E for sample S3. (55Cl beam, 50MeV)
Robin Round characterization of the thickness and composition of thin to ultra-thin AlNO films
Samples provided by ITN - Portugal.
Si
Effects of thin film roughness on RBS spectraAlessandro A.da Silva, M.H. Tabacniks (IFUSP)
• By changing detection angle the assumed relationship 1/cos(), for the film thickness, is not obeyed due to topographical effects
• Two detectors at different angles, measure different surfaces, thus different roughness, and different film thickness
• It might be possible to distinguish thin film diffusion effects from surface roughness just by tilting the sample or changing the detector angle
AMS analysis of geological and biological samplesN.Added, J.C. Acquadro, R. Liguori Neto, M.A. Rizutto (IFUSP) P.R.S. Gomes, R.M. dos Anjos (UFF), C.R. Appoloni, M.M. Coimbra (UEL), G.M.Santos, K. Fifield (ANU).
b)
a)
Typical AMS energy spectra
a) 14C from sample and contaminants from setup.
b) Energy calibration spectrum: three charge states of 12C after bombarding a 120Sn + 197Au target.
Experimental curves for energy loss of ions in matterR. Liguori Neto, N. Added, F.A.S. Coutinho (IFUSP)
Graphical example ilustrating the method a) Ef and E without foil and b) Ef’and E’with mylar foil. Hatched area indicates the same number of particles in both spectra.
)('
)(')('
'
EEEEwhere
dEEfdEEfff E
E
E
E
Modification of a Si deviceN.Added, M.H. Tabacniks (IFUSP)
• high energy proton implantation in air
• defects in Si increase e- mobility and device frequency
• during implantation device testing possible
80 µm Si(n) contact
200µm Si substrate
5 to 6 MeV proton beam <1016/cm2
top of device
Sr/Ca ratio in shells for a temperature sensorElisa Ferreira, M.A. Rizutto, N. Added, M.H. Tabacniks (IFUSP)
Shells collected at different sites with different temperaturesSr and Ca measured by PIXE and PIGE
CARACTERIZAÇÃO ESPECTROSCÓPICA DE PRODUTOS DE CORROSÃO DE DUAS PEÇAS METÁLICAS DO MAE-USP
Carlos R. Appoloni, Paulo S. Parreira Laboratório de Física Nuclear Aplicada, Departamento de Física, Universidade Estadual de Londina., BrasilManfredo H. Tabacniks, Márcia A. Rizzutto, Nemitala Added, Laboratório de Análise de Materiais por Feixes Iônicos, Instituto de Física, Universidade de São Paulo, Brasil Silvia Cunha Lima, Laboratório de Conservação e Restauro, Museu de Arqueologia e Etnologia, Universidade de São Paulo, BrasilHercílio G. de Melo, Augusto C. Neiva, Rocio P. Bendezú H. Laboratório de Eletroquímica e Corrosão, Departamento de Engenharia Química, Escola Politécnica, Universidade de São Paulo, Brasil
A primeira aplicação do arranjo experimental de feixe externo foi a análise de artefatos arqueológicos do MAE (Museu de Arqueologia e Etnologia da Universidade de São Paulo).
Ar
S Cu
Zn
SiNiFe
KCa
conclusions(Nuclear) Applied physics can be part of the bridge connecting basic physics with the “real world” (Remember: It is a two way connection !)
Timing: Nuclear applied physics with accelerators started at IFUSP in 1980 with PIXE applied to air pollution research at the 8MeV Pelletron accelerator. 1992 started LAMFI. 2000 began the Group for Applied Physics with accelerators.
Do not do: “ Given a solution (my accelerator), what is the problem?”Seek the right solutions to your problem.
Facilities must work on a continuous basis. (Time is a working variable)
Work in collaboration: Physicists don´t need to know everything, but avoid to be a “service” laboratory.